Boris Johnson has said the UK should not be afraid of life outside the EU if a better deal cannot be negotiated with other European countries.

In a major speech responding to a report the London mayor commissioned from his economic adviser Gerard Lyons, Mr Johnson supported David Cameron's desire to negotiate reforms to the EU in Britain's interest.

But he argued if the attempts at reform fail, there is an "attractive" option without EU membership.

"We could negotiate a generous exit, securing European Free Trade Association-style access to the Common Market," he said.

"There is nothing to be afraid of in going for an alternative future," he insisted, pointing to the possibility of "a Britain open not just to the rest of Europe but to the world... if we get it right it's a win-win".

The question Tories will ask themselves is whether Boris Johnson is positioning himself as a standard bearer for the Eurosceptic wing of the party.

Image:The mayor will lend his support to Mr Cameron's push for EU reform

On that front, with such a heavily caveated position, the answer needs to be seen as yes and no.

There is every chance that with pent up expectation within the party, the mayor may be accused of being something of a tease on the Europe front - not an unaccustomed position.

The mayor's desire is to show that he is grappling in a serious way with a very tricky issue, and if in the process he shows a bit of ankle to Eurosceptics in the Conservative Party, so much the better.